|Pos|No|Driver|Constructor|Laps|Time/Retired|Grid|Points|
|---|---|---|---|---|---|---|---|
|1|4|Robert Kubica|BMW Sauber|70|1:36:24.227|2|10|
|2|3|Nick Heidfeld|BMW Sauber|70|+16.495|8|8|
|3|9|David Coulthard|Red Bull-Renault|70|+23.352|13|6|
|4|12|Timo Glock|Toyota|70|+42.627|11|5|
|5|2|Felipe Massa|Ferrari|70|+43.934|6|4|
|6|11|Jarno Trulli|Toyota|70|+47.775|14|3|
|7|17|Rubens Barrichello|Honda|70|+53.597|9|2|
|8|15|Sebastian Vettel|Toro Rosso-Ferrari|70|+54.120|19|1|
|9|23|Heikki Kovalainen|McLaren-Mercedes|70|+54.433|7||
|10|7|Nico Rosberg|Williams-Toyota|70|+54.749|5||
|11|16|Jenson Button|Honda|70|+1:07.540|20||
|12|10|Mark Webber|Red Bull-Renault|70|+1:11.299|10||
|13|14|Sébastien Bourdais|Toro Rosso-Ferrari|69|+1 Lap|18||
|Ret|21|Giancarlo Fisichella|Force India-Ferrari|51|Spun off|17||
|Ret|8|Kazuki Nakajima|Williams-Toyota|46|Accident|12||
|Ret|5|Fernando Alonso|Renault|44|Spun off|4||
|Ret|6|Nelson Piquet Jr.|Renault|43|Brakes|15||
|Ret|1|Kimi Räikkönen|Ferrari|19|Collision|3||
|Ret|22|Lewis Hamilton|McLaren-Mercedes|19|Collision|1||
|Ret|20|Adrian Sutil|Force India-Ferrari|13|Gearbox|16||

Question: how many cars spun off the track?
Answer: 2